Preheat the oven to 375°F (190°C).
In a bowl, combine all the meatball ingredients until mixed well.
Prepare your casserole, then shape about 2 tbsp beef mixture into a round shape. Then arrange the meatball into the casserole so the meatball will cook evenly.
Bake for 15 minutes, then transfer the cooked meatballs to a bowl. When the meatballs are baked, there will be juice from the beef, mix the juice with the cooked rice, because it will make the rice taste more savory.
On a casserole from cooking meatballs before, add cooked rice, sour cream, tomato paste, parmesan cheese, italian seasoning, salt, and black pepper. With a spoon, mix until all the ingredients are well combined.
Add ¼ of the mozzarella cheese, then mix until just combined.
Flatten the rice, then arrange the meatballs on top of the rice. Sprinkle mozzarella cheese over the meatballs evenly, then bake again for 40-45 minutes.
Before serving, sprinkle the meatball rice casserole with chopped parsley. Enjoy!